Pronunciation: [nˌɒt lˈiːst] (IPA) 
"Not least" is a common English phrase that is spelled using the letters N-O-T followed by L-E-A-S-T. The two words are pronounced with stress on the second syllable of "least," and the "ea" is pronounced with a long "e" sound. In IPA phonetic transcription, this phrase is represented as /nɒt liːst/. The phrase is often used to indicate that something is significant or important, even if it may not be the most important thing.
"Not least" is an idiomatic expression used to emphasize the significance or importance of a particular aspect or factor within a larger context. It is often employed when discussing a list or series of things, indicating that the mentioned element holds special or noteworthy significance compared to the others.
One possible definition of "not least" is that it refers to something that should not be overlooked or underestimated. It implies that the mentioned item is of considerable importance or contributes significantly to a situation, despite also acknowledging the significance of other factors. The phrase can be used both in positive and negative contexts.
For example, consider a sentence like, "The success of the project can be attributed to various factors, including effective team coordination, adequate funding, and not least, the innovative approach taken by the lead developer." Here, "not least" emphasizes that the innovative approach played a vital role in the success of the project, alongside other mentioned factors.
Overall, "not least" functions as a way to draw attention to a particular element or factor within a list or series, indicating its essential or notable nature in comparison to the others.
The term "not least" can be seen as a combination of two separate words: "not" and "least".
The word "not" originates from the Old English word "nāt", which meant "not" or "not at all". This word eventually evolved into the Middle English word "nat" and later "not" with the same meaning.
On the other hand, the word "least" comes from the Old English word "lǣst", meaning "smallest" or "the smallest part". It can be traced back to the West Germanic word "laisistaz" and the Proto-Germanic word "laistiz".
When these two words are combined, "not least" is used to indicate that something mentioned is especially important or significant, implying that it should not be considered the smallest or least important aspect.
